Preheat grill pan over medium heat, using a silicone brush, oil the grill grates. Place the patties on the grill pan, cook on first side until grill marks are achieved and the patties release easily from the pan, about 4 minutes. Flip, and top each patty with queso fresco, and cook on second side, covering if needed to melt the cheese, until an instant read thermometer inserted into the middle of the patty ready 165°.